/**
 * Enrich ESPN / Odido-ESPN events with artwork from ESPN Watch NL product API.
 * Match: ESPN•channel hint + time proximity + title/subtitle tokens.
 */

import {
  normalizeTitleTokens,
  titleOverlapScore,
  type EnrichableEvent,
} from "./ziggo-epg-art";

const BUCKET_IDS = ["39622"]; // Komende Wedstrijden (NL watch)
const API_KEY = "1ngjw23osgcis1i1vbj96lmfqs"; // public web apikey from espn.nl
const FETCH_TIMEOUT_MS = 12_000;
const CACHE_TTL_MS = 15 * 60_000;

export type EspnWatchEvent = {
  id: string;
  name: string;
  subtitle: string;
  catalog: string;
  utcMs: number;
  imageHref: string;
  channelHint: string | null; // ESPN / ESPN2 / …
};

type CacheState = {
  at: number;
  events: EspnWatchEvent[];
};

let cache: CacheState | null = null;

export function invalidateEspnWatchArtCache() {
  cache = null;
}

export function isEspnRelated(e: {
  provider?: string;
  channel?: string | null;
  network?: string | null;
  name?: string;
}): boolean {
  const p = (e.provider ?? "").toLowerCase();
  if (p === "espn") return true;
  const blob = `${e.channel ?? ""} ${e.network ?? ""} ${e.name ?? ""}`.toLowerCase();
  return /\bespn\s*\d?\b/.test(blob);
}

export function needsEspnArtEnrichment(e: {
  provider?: string;
  channel?: string | null;
  network?: string | null;
  name?: string;
  imageLandscape?: string | null;
  images?: string[];
}): boolean {
  if (!isEspnRelated(e)) return false;
  if (!e.imageLandscape && !(e.images?.length)) return true;
  // Replace weak logos if present without real art
  if (e.imageLandscape && /logo|assets\/channels/i.test(e.imageLandscape) && !(e.images ?? []).some((u) => /artwork\.api\.espn|artwork\.espncdn/i.test(u))) {
    return true;
  }
  return false;
}

export function parseEspnChannelHint(subtitle: string | null | undefined): string | null {
  const s = String(subtitle ?? "");
  const m = s.match(/\b(ESPN\s*\d?)\b/i);
  if (!m) return null;
  return m[1].replace(/\s+/g, "").toUpperCase().replace(/ESPN$/, "ESPN");
}

export function normalizeEspnChannel(name: string | null | undefined): string | null {
  const s = String(name ?? "").trim();
  if (!s) return null;
  const m = s.match(/\b(ESPN\s*\d?)\b/i);
  if (!m) return null;
  return m[1].replace(/\s+/g, "").toUpperCase().replace(/ESPN$/, "ESPN");
}

/** Widen imageHref to a useful card width. */
export function normalizeEspnArtUrl(href: string): string {
  try {
    const u = new URL(href);
    if (!u.searchParams.has("width")) u.searchParams.set("width", "960");
    else u.searchParams.set("width", "960");
    if (!u.searchParams.has("apikey") && /artwork\.api\.espn\.com/i.test(u.host)) {
      u.searchParams.set("apikey", API_KEY);
    }
    return u.toString();
  } catch {
    return href;
  }
}

export function pickBestEspnMatch(
  candidates: EspnWatchEvent[],
  opts: {
    title: string;
    startMs: number;
    endMs: number;
    channel?: string | null;
    network?: string | null;
  }
): EspnWatchEvent | null {
  const wantCh =
    normalizeEspnChannel(opts.channel) ||
    normalizeEspnChannel(opts.network) ||
    normalizeEspnChannel(opts.title);
  let best: EspnWatchEvent | null = null;
  let bestScore = 0;
  for (const c of candidates) {
    if (!c.imageHref) continue;
    // Time: prefer start within window; summaries may be hours offset — allow 12h
    const mid = (opts.startMs + opts.endMs) / 2;
    const dt = Math.abs(c.utcMs - mid);
    if (dt > 12 * 60 * 60 * 1000) continue;

    const hay = `${opts.title}`;
    const zig = `${c.name} ${c.subtitle} ${c.catalog}`;
    let score = titleOverlapScore(hay, zig);
    if (wantCh && c.channelHint) {
      if (wantCh === c.channelHint) score += 0.25;
      else score -= 0.15;
    }
    // Time proximity bonus (closer = better)
    score += Math.max(0, 0.3 - dt / (12 * 60 * 60 * 1000) * 0.3);
    if (score > bestScore) {
      bestScore = score;
      best = c;
    }
  }
  return bestScore >= 0.28 ? best : null;
}

async function fetchJson<T>(url: string): Promise<T | null> {
  const ac = new AbortController();
  const timer = setTimeout(() => ac.abort(), FETCH_TIMEOUT_MS);
  try {
    const res = await fetch(url, {
      signal: ac.signal,
      headers: {
        Accept: "application/json",
        "User-Agent": "VMC-master/1.0",
      },
    });
    if (!res.ok) return null;
    return (await res.json()) as T;
  } catch {
    return null;
  } finally {
    clearTimeout(timer);
  }
}

function walkEvents(node: unknown, out: EspnWatchEvent[]) {
  if (!node || typeof node !== "object") return;
  if (Array.isArray(node)) {
    node.forEach((x) => walkEvents(x, out));
    return;
  }
  const o = node as Record<string, unknown>;
  if (o.isEvent === true && o.name && o.imageHref) {
    const utcRaw = String(o.utc ?? o.date ?? "");
    const utcMs = Date.parse(utcRaw);
    if (Number.isFinite(utcMs)) {
      const catalog = Array.isArray(o.catalog)
        ? (o.catalog as Array<{ name?: string }>)
            .map((c) => c.name ?? "")
            .filter(Boolean)
            .join(", ")
        : "";
      out.push({
        id: String(o.id ?? ""),
        name: String(o.name),
        subtitle: String(o.subtitle ?? ""),
        catalog,
        utcMs,
        imageHref: String(o.imageHref),
        channelHint: parseEspnChannelHint(String(o.subtitle ?? "")),
      });
    }
  }
  for (const v of Object.values(o)) walkEvents(v, out);
}

async function loadEspnIndex(): Promise<CacheState | null> {
  if (cache && Date.now() - cache.at < CACHE_TTL_MS) return cache;

  const events: EspnWatchEvent[] = [];
  const seen = new Set<string>();
  await Promise.all(
    BUCKET_IDS.map(async (bucketId) => {
      const url =
        `https://watch.product.api.espn.com/api/product/v3/watchespn/web/bucket` +
        `?lang=nl&deviceBrand=web&bucketId=${bucketId}&countryCode=NL&tz=UTC%2B0200&features=pbov7`;
      const j = await fetchJson<unknown>(url);
      if (!j) return;
      const batch: EspnWatchEvent[] = [];
      walkEvents(j, batch);
      for (const e of batch) {
        if (!e.id || seen.has(e.id)) continue;
        seen.add(e.id);
        events.push(e);
      }
    })
  );

  if (!events.length) return cache;
  cache = { at: Date.now(), events };
  return cache;
}

export async function enrichEspnWatchArt<T extends EnrichableEvent & { provider?: string }>(
  events: T[]
): Promise<T[]> {
  const targets = events.filter(needsEspnArtEnrichment);
  if (!targets.length) return events;

  const index = await loadEspnIndex();
  if (!index?.events.length) return events;

  return events.map((e) => {
    if (!needsEspnArtEnrichment(e)) return e;
    const startMs = Date.parse(e.start);
    const endMs = Date.parse(e.stop);
    if (!Number.isFinite(startMs) || !Number.isFinite(endMs)) return e;

    const match = pickBestEspnMatch(index.events, {
      title: e.name,
      startMs,
      endMs,
      channel: e.channel,
      network: e.network,
    });
    if (!match) return e;

    const art = normalizeEspnArtUrl(match.imageHref);
    const images = [art, ...e.images.filter((u) => u !== art)];
    return {
      ...e,
      imageLandscape: art,
      imageBackdrop: e.imageBackdrop || art,
      images,
    };
  });
}

// re-export for tests that want token helpers
export { normalizeTitleTokens, titleOverlapScore };